Communicating paging information in wireless communications

ABSTRACT

Systems, devices, and techniques are described for performing paging in a wireless communication network. A method includes mapping a paging indication to one or more resource elements. The one or more resource elements are resources in one or more synchronization signal symbols that are not mapped by the synchronization signal. The method includes transmitting the paging indication to trigger a response from a user equipment for performing subsequent paging.

CROSS REFERENCE TO RELATED APPLICATIONS

This patent document is a continuation of and claims benefit of priorityto U.S. patent application Ser. No. 16/785,645, filed Feb. 9, 2020,which is a continuation of International Patent Application No.PCT/CN2017/097179, filed on Aug. 11, 2017. The entire content of thebefore-mentioned patent applications is incorporated by reference aspart of the disclosure of this application.

TECHNICAL FIELD

This application relates to systems, devices, and techniques forwireless communications.

BACKGROUND

A wireless communication network of base stations provides wirelesscommunications to mobile stations or other wireless devices, which aregenerally referred to as user equipment, by using downlinkcommunications channels to send information to the user equipment anduplink communications to receive information from the user equipment.The wireless network and the user equipment are designed to allow theuser equipment to be in a power saving mode (e.g., an idle mode) toreduce the user equipment activities for saving power. The base stations(or the base station controllers) can send paging messages to userequipment to wake up the user equipment from the power saving mode.

SUMMARY

This document describes technologies, among others, for communicatingand using timing information related to paging user equipment in awireless communications network.

According to some embodiments, a method for paging user equipment in awireless network is provided. The method includes mapping a pagingindication to one or more resource elements. The one or more resourceelements are resource elements in one or more synchronization signalsymbols that are not mapped by the synchronization signal. The methodincludes transmitting the paging indication to trigger a response from auser equipment for performing subsequent paging.

According to some embodiments, the method includes the one or moreresource elements including one or more continuous pluralities ofresource elements without a demodulation reference signal mapped to aresource element of the continuous plurality of resource elements.

According to some embodiments, the method includes mapping ademodulation reference signal to one or more resource elements in one ormore physical broadcast channel symbols that are adjacent to at leastone of the one or more synchronization signal symbols. The demodulationreference signal provides a reference signal for demodulating the pagingindication. The paging indication shares a same antenna port with theone or more physical broadcast channel symbols.

According to some embodiments, the method includes the one or moreresource elements being outside a bandwidth of the one or moresynchronization signals. The one or more resource elements are inside abandwidth of one or more physical broadcast channels.

According to some embodiments, the method includes transmitting ademodulation reference signal in a second one or more resource elements.The second one or more resource elements are in one or more physicalbroadcast channel symbols. The second one or more resource elements areoutside the bandwidth of the one or more synchronization signals. Thesecond one or more resource elements are inside the bandwidth of the oneor more physical broadcast channel. The demodulation reference signalprovides a reference signal for demodulating the paging indication.

According to some embodiments, the method includes the paging indicationincluding an indicator of a paging transmission mode. The pagingtransmission mode is a mode by which a paging message is to betransmitted.

According to some embodiments, the method includes selecting the pagingtransmission mode from among a plurality of available transmissionmodes.

According to some embodiments, the method includes mapping a pagingreason category indication information to the one or more resourceelements.

According to some embodiments, the method includes receiving one or moreresponses to the paging indication from one or more user equipment. Themethod further includes transmitting one or more paging messages basedon information received in the one or more responses.

According to some embodiments, the method includes transmitting thepaging indication using a plurality of antenna ports. The method furtherincludes receiving one or more responses to the paging indication fromone or more user equipment. Each response indicates at least one antennaport. The method further includes transmitting one or more pagingmessages using the antenna ports indicated in the responses. The one ormore paging messages are not transmitted using other antenna port notindicated in the responses.

According to some embodiments, the method includes determining a groupof user equipment to which one or more user equipment to page belong.The paging indication includes an indicator for the group of userequipment.

According to some embodiments, a method is provided for responding topaging by a user equipment in a wireless network. The method includesreceiving a paging indication in one or more resource elements. The oneor more resource elements are resource elements in one or moresynchronization signal symbols that are not mapped by thesynchronization signal. The paging indication triggers a response fromthe user equipment to perform subsequent paging.

According to some embodiments, the method includes the one or moreresource elements including one or more continuous pluralities ofresource elements without a demodulation reference signal mapped to aresource element of the continuous plurality of resource elements.

According to some embodiments, the method includes receiving ademodulation reference signal in one or more resource elements in one ormore physical broadcast channel symbols that are adjacent to at leastone of the one or more synchronization signal symbols. The demodulationreference signal provides a reference signal for demodulating the pagingindication. The paging indication shares a same antenna port with theone or more physical broadcast channels.

According to some embodiments, the method includes the one or moreresource elements being outside a bandwidth of the one or moresynchronization signals, and wherein the one or more resource elementsare inside a bandwidth of one or more physical broadcast channels.

According to some embodiments, the method includes receiving ademodulation reference signal in a second one or more resource elements.The second one or more resource elements are in one or more broadcastchannel signal symbols. The second one or more resource elements areoutside the bandwidth of the one or more synchronization signals. Thesecond one or more resource elements are inside the bandwidth of the oneor more broadcast channel signals. The demodulation reference signalprovides a reference signal for demodulating the paging indication.

According to some embodiments, the method includes the paging indicationincluding an indicator of a paging transmission mode. The pagingtransmission mode is a mode by which a paging message is to betransmitted.

According to some embodiments, the method includes the pagingtransmission mode being selected from among a plurality of availabletransmission modes.

According to some embodiments, the method includes mapping a pagingreason category indication information to the one or more resourceelements.

According to some embodiments, the method includes transmitting aresponse to the paging indication. The method further includes receivingone or more paging messages that are transmitted based on informationtransmitted in the response and zero or more other responses.

According to some embodiments, the method includes receiving the pagingindication in a space corresponding to one antenna port of a pluralityof antenna ports over which the paging indication was transmitted. Themethod further includes transmitting a response to the pagingindication. The response and zero or more other responses from otheruser equipment indicate at least one antenna port. The method furtherincludes receiving one or more paging messages in a space correspondingto one of the at least one indicated antenna ports. The one or morepaging messages are transmitted using the antenna ports indicated in theresponses.

According to some embodiments, the method includes receiving the pagingindication. The paging indication includes an indicator for a group ofuser equipment determined based on incoming data information indicatinga user equipment to page. The paging indication does not include anindicator for at least one other group of user equipment.

BRIEF DESCRIPTION OF THE DRAWINGS

FIG. 1 is a diagram showing an example wireless communications system.

FIG. 2 is a block diagram showing an example of a wireless communicationapparatus 200.

FIG. 3 is a diagram showing an example wireless communications systemthat employs beamforming.

FIG. 4 is a sequence diagram showing a process for triggering pagingactivity.

FIG. 5 is a diagram showing a wireless communications system that uses aprocess to trigger paging activity.

FIG. 6 is a diagram showing resource element allocation tosynchronization and broadcast channels.

FIG. 7 is a diagram showing resource element allocation tosynchronization and broadcast channels.

FIG. 8 is a diagram showing resource element allocation tosynchronization and broadcast channels.

FIG. 9 is a diagram showing resource element allocation tosynchronization and broadcast channels.

FIG. 10 is a diagram showing resource element allocation tosynchronization and broadcast channels.

FIG. 11A is a diagram of a data structure for transmitting paging reasoncategory indication information.

FIG. 11B is a diagram of a data structure for transmitting paging reasoncategory indication information.

FIG. 11C is a diagram of a data structure for transmitting paging reasoncategory indication information.

FIG. 11D is a diagram of a data structure for transmitting paging reasoncategory indication information.

FIG. 12 is a diagram of a data structure for transmitting user equipmentindication information.

FIG. 13 is a diagram of a data structure for transmitting user equipmentindication information and paging reason category indicationinformation.

FIG. 14 is a sequence diagram of a process for paging transmission.

FIG. 15 is a sequence diagram of a process for paging transmission.

FIG. 16 is a sequence diagram of a process for paging transmission.

FIG. 17 is a flowchart of a process for paging transmission usingmultiple paging transmission modes.

FIG. 18 is a flowchart of a process for paging transmission usingmultiple paging transmission modes.

Like reference symbols in the various drawings indicate like elements.

DETAILED DESCRIPTION

Due to continuous progress in radio technology, a wide range of wirelessapplications have emerged and continue to emerge, which has led to agrowth in wireless deployments. However, traditional technologies arefalling short of meeting such an increased demand, at least because thespectrum resource of approximately 300 MHz to 3 GHz is provinginsufficient to meet the ever-increasing bandwidth demands based oncurrent technologies. Thus techniques are needed to improve theefficiency with which bandwidth is used to support wirelessapplications. The disclosed techniques for paging can be used forefficient bandwidth utilization in wireless communications, e.g.,improving resource utilization in connection with use of multipleantennas for transmission and/or reception by sending a pagingindication from a base station to the user equipment prior to paging theuser equipment of various users served by the base station.

FIG. 1 is a diagram showing an example wireless communications system100. The system 100 includes a base station 102 and multiple userequipment 106 being able to communicate with each other over atransmission medium 104. The transmissions from the base station 102 tothe user equipment 106 are generally called downlink or downstreamtransmissions. The transmissions from the user equipment 106 to the basestation 102 are generally called uplink or upstream transmissions. Thetransmission medium 104 is typically a wireless (air) medium. The basestation 102 may also be communicatively coupled with other base stationsor other equipment in the network via a backhaul or an access networkconnection 112.

FIG. 2 is a block diagram showing an example of a wireless communicationapparatus 200. The wireless communication apparatus 200 may be providedas a user equipment (e.g., user equipment 106), as a base station (e.g.,base station 102), or otherwise. The apparatus 200 includes a processor210 that may be configured to implement one of the techniques describedherein, transceiver electronics 215 that is able to transmit signals orreceive signals using the antenna(s) 220, and one or more memories 205that may be used to store instructions executable by the processor 210and/or data storage.

One way that the problem of insufficient bandwidth may be addressed isto use a different bandwidth than has traditionally been used forwireless applications. For instance wireless communications could use acarrier frequency in the range of 28 GHz, 45 GHz, 70 GHz, etc., each ofwhich is considerably higher than the carrier frequencies used by theexisting fourth generation (4G) communications systems.

This higher carrier frequency introduces some challenges, such as alarger transmission path loss, the signal is easily absorbed by oxygen,the signal is easily affected by rain attenuation, etc., each of whichseriously affects performance of such a high frequency communicationssystem.

However, higher carrier frequency also introduces benefits. Forinstance, because the higher frequency has a shorter wavelength, it ispossible to use shorter antennas, thus allowing the use of more antennaelements per unit of area. With more antenna elements, beamforming canbe used to improve antenna gain, which can be used to offset theperformance losses of the high frequency signal.

With beamforming, a transmitter is able to concentrate the emission ofenergy in a particular direction, while in other directions the energyis small or absent. This means that each beam has a directivity, thatis, it covers a certain direction or physical space and the userequipment (e.g., user equipment 106) that are present therein. It isforeseeable that a base station (e.g., base station 102) could employdozens or even hundreds of antennas, thus supporting transmission todozens or hundreds of spatially-independent (or at least partiallyindependent) directions within the same cell.

FIG. 3 is a diagram showing an example wireless communications system300 the employs beamforming. The system 300 may be provided aspreviously described (e.g., wireless communication system 100). Further,the system 300 includes a base station 302 in communication with userequipment 312, user equipment 314, user equipment 316, and userequipment 318. The base station 302 may be provided as previouslydescribed (e.g., base station 102, wireless transmission apparatus 200).The user equipment 312, 314, 316, 318 may each be provided as previouslydescribed (e.g., user equipment 106, wireless transmission apparatus200).

The base station 302 includes antenna 322, antenna 324, antenna 326, andantenna 328. The antennas 322, 324, 326, and 328 may be provided aspreviously described (e.g., antenna 220). The base station 302 and theantennas 322, 324, 326, 328 employ beamforming into direction 332,direction 334, direction 336, and direction 338. In particular, one ormore antennas of 322, 324, 326, and 328 employ beamforming with specificweights in order to emit energy in the direction 332 (illustrated byhashed lines) but emits little or no energy outside of the direction332. Because the user equipment 312 is within the direction 332, asignal transmitted by the base station 302 in the direction 332 would bereceived by the user equipment 332. But, because the user equipment 312is not within the direction 334, the direction 336, or the direction338, a signal transmitted by the base station 302 in any of thedirections 334, 336, 338 would not be received by the user equipment312.

Each of directions 332, 334, 336, 338 may alternatively be referred toas antenna ports, which may be a logical identifier that the basestation 302 associates with a given antenna port/direction. In otherembodiments, antenna ports may correspond to a mapping of weights to beapplied to one or more of the antennas 322, 324, 326, 328. For example,an additional antenna port may be defined based on partial emission bythe antennas 322, 324 and no emission by the antennas 326, 328. Thus anantennas port may correspond to a single one of the antennas 322, 324,326, 328 or to combinations of the antennas 322, 324, 326, 328 withaccompanying weights.

It should be understood that the illustration of FIG. 3 is onlyexemplary. In some embodiments, the directions 332, 334, 336, 338 may bedefined in three dimensions (rather than the two dimensions shown).Additionally, the base station 302 may employ tens, hundreds, or moreantennas (rather than the four antennas shown). Additionally, the basestation may transmit signals in tens, hundreds, or more directions(rather than the four directions shown). Additionally, the directions332, 334, 336, 338 may partially or wholly overlap (rather than beingwholly spatially distinct as shown). Additionally, the base station 302may communication with tens, hundreds, or more user equipment (ratherthan the four user equipment shown).

Beamforming presents a benefit of allowing a base station to transmit amessage in only one direction, while leaving the bandwidth in otherdirections unused or available for other messaging. For example, if thebase station 302 has a message to transmit to the user equipment 312,then the base station can use transmit that message in only thedirection 332 while leaving the bandwidth in the directions 334, 336,338 available for messaging to the user equipment 314, 316, 318 presentin those respective directions. While there are some limitations to thisbenefit due to interference and other concerns, beamforming essentiallyallows a base station and the wireless communications system of which itis a part to multiple the messaging capacity many times withoutincreasing the spectrum used.

But this solution also present a new challenge. In particular, in orderto realize the benefit just described, the base station 302 must knowthat the user equipment 312 is present in the direction 332, as opposedto being present in one of the directions 334, 336, 338. But the basestation 302 may not always have this information, as describe furtherbelow.

In particular, the user equipment 312 may enter a power saving mode suchas an idle state after having initially communicated with the basestation 302. A discontinuous reception mode (DRX) can be implemented inthe idle state in the paging the user equipment. The user equipment 312may enter the idle state when it does not have any information totransmit to the base station 302. The user equipment 312 may enter theidle state in order to reduce the draw on a battery providing electricalcharge to the user equipment 312. But while the user equipment 312 is inthe idle state, the base station 302 may receive information from thenetwork that needs to be transmitted to the user equipment 312 (e.g.,there is an incoming call for the user equipment 312, downlink dataarriving indication, system message change, receiving emergency warning(EWTS), receiving mobile alert (CMAS)). In order to alert the userequipment 312 of this incoming data, the base station 302 may use apaging mechanism.

With the paging mechanism, the user equipment 312 may “wake up”according to a predetermined schedule and check a downlink pagingchannel for any paging message. If the user equipment 312 detects apaging message during one of these observations of the paging channel,then the user equipment 312 is alerted to the presence of incoming datafor the user equipment 312 at the base station 302, and proceedsaccordingly. As such, when the base station 302 receives informationfrom the network that needs to be transmitted to the user equipment 312,the base station 302 transmits a paging message on the paging channelaccording to the predetermined schedule of the user equipment 312. Thebase station 302 generally knows this predetermined schedule (e.g., theuser equipment 332 notifies the base station 302 of its paging scheduleprior to entering idle mode).

In the existing LTE systems, when a base station has paging informationto transmit to a user equipment, the base station notifies all userequipment within the base station's cell that a paging message is beingtransmitted. The base station sends this notification by scrambling asignal in the physical downlink control channel (PDCCH) with a specialfixed value called the paging radio network temporary identifier(P-RNTI). This alerts all user equipment in the cell (that were awake tomonitor the PDCCH at that time) that a paging message is included in thesame subframe transmission, specifically, in the paging control channel(PCCH), which is a logical channel mapped to the paging channel (PCH),which is a transport channel mapped to the physical downlink sharedchannel (PDSCH).

Thus, the base station 302 generally knows when to transmit a pagingmessage for the user equipment 312. But with beamforming, the basestation 302 does not necessarily know where to transmit the pagingmessage for the user equipment 312. This is because the user equipment312 may move around inside the cell serviced by the base station 302. Asa result, the user equipment 312 may be present at the time of paging ina different direction (e.g., the direction 332) than the direction thatthe user equipment 312 was in at the time of entering the idle state(e.g., the direction 334).

In fact, there is a further complication to the problem. Theoretically,the base station 302 could transmit the paging message to all of thedirections 332, 334, 336, 338 at the same time (i.e., at the time theuser equipment 312 is awake and monitoring the paging channel), eventhough this would undo some of the bandwidth-savings benefit describedpreviously. This may be referred to as a sweeping or beam sweepingtechnique. However, practical limitations in the transceiver hardwarefor the base station 302 generally make it impossible to transmit on somany antennas at the same time. Thus, the base station 302 would have tostagger transmission of the paging message to the directions 332, 334,336, 338. This then complicates the ability of the base station 302 totransmit the paging message while the user equipment 312 is monitoringthe paging channel (i.e., the base station 302 may not transmit thepaging message while the user equipment 312 is monitoring the pagingchannel, depending on which of the directions 332, 334, 336, 338 theuser equipment 312 is located). Thus while application of a beamsweeping technique is possible using existing systems, it is notefficient. This is described in further detail below.

In a beam-based transmission system, the beam direction of differentsubframes/timeslots is based on the flexible configuration of theservice. According to the paging mechanism existing system (e.g., LTE),it is necessary to load the paging message within the transmissionsubframe/slot corresponding to each beam, which means that the userequipment paging message reception for different beams will bedistributed to multiple subframes/slots within the paging cycle. Unlikewith such existing systems, the paging control information (DCI) and thepaging message are not necessarily transmitted in the same subframe.Thus, the structure of the above-mentioned beam scan is introduced topoll transmitting in each beam direction. Such beam scan transmissionstructure means higher reception complexity and energy overhead for theuser equipment, it also means greater downlink resource overhead for thebase station and the network. Therefore, efficient transmission ofpaging-related control information is required in order to avoidunnecessary paging transmission and reception. In particular, what isneeded is a technique to trigger a user equipment to begin a pagingprocess, with the technique being both efficient in terms of userequipment energy consumption (i.e., idle time versus wake time) andefficient in terms of use of spectrum resources for the cell (i.e.,amount of bandwidth used).

FIG. 4 is a sequence diagram showing a process 400 for triggering pagingactivity. The process 400 involves a network 406, a base station 402(e.g., as described for base station 102, 302, wireless communicationapparatus 200), and a user equipment 404 (e.g., as described for userequipment 106, 312, wireless communication apparatus 200).

The network 406 transmits incoming data information 422 to the basestation 402. The incoming data information 422 may include informationidentifying a particular user equipment (e.g., user equipment 404), agroup of user equipment, or all user equipment for which incominginformation is available.

In response to receiving the incoming data information 422, the basestation 402 transmits a paging indication 424 to user equipment 404. Thepaging indication 424 may include an indicator as to which userequipment (e.g., a specific user equipment, a group of user equipment)should respond to the base station 402 in order to perform subsequentpaging.

In response to receiving the paging indication 424, the user equipment404 transmits a response 426 to the base station 402. The response 426may include information relating to a manner in which the base station402 can transmit a paging message to the user equipment 404. Forexample, the response 426 may include identification of a beamformingdirection (e.g., identification of a direction, identification of anantenna, identification of an antenna port) where the user equipment 404is presently located.

The base station 402 and the user equipment 404 performing paging 428based on the exchange of the paging indication 424 and the response 426.For example, the paging 428 may include the user equipment monitoring aresource for a paging message in accordance with identificationinformation in the paging indication 424. And, the base station 402 maytransmit a paging message in accordance with identification informationin the response 426 (e.g., transmitting the paging message to only theantenna port identified by the response 426).

FIG. 5 is a diagram showing a wireless communications system 500 thatuses a process to trigger paging activity. The system 500 includes basestation 502 (e.g., as described for base station 102, 302, 402, wirelesscommunication apparatus 200) and user equipment 512, 514, 516, 518(e.g., as described for user equipment 106, 312, 404, wirelesscommunication apparatus 200). The base station 502 includes antennas522, 524, 526, 528 (e.g., as described for antennas 220, 322, 324, 326,328). The base station 502 transmits signals using beamforming with theantennas 522, 524, 526, 528 in directions 532, 534, 536, 538,respectively.

The base station 502 may receive incoming data information (e.g., asdescribed with respect to incoming data information 422). The incomingdata information may identify the user equipment 512 as having incomingdata from the network. If the user equipment 512 is in the idle state,then the base station 502 does not necessarily know in which directionof the directions 532, 534, 536, 538 the user equipment 512 is present.

The base station 502 may then transmit a paging indication 542 in allthe directions 532, 534, 536, 538 (i.e., using all of the antennaports). The paging indication 542 may indicate that the user equipment512 should respond in order to perform subsequent paging. Alternativelythe paging indication 542 may indicate that all members of a group ofuser equipment, of which the user equipment 512 is a member, shouldrespond in order to perform subsequent paging.

As a result of receiving the paging indication 542, the user equipment512 may send a response 544 to the base station 502. For example, theresponse 544 may indicate that the user equipment 512 is in thedirection 532.

As a result of receiving the paging indication 542, the user equipment514, 516, 518 may not respond to the base station 502. For example, theuser equipment 514, 516, 518 may not be members of a group to which thepaging indication 542 pertains.

As a result of receiving the response 544, the base station 502 maytransmit a paging message 546 using the antenna port for the direction532. The base station 502 may not transmit the paging message 546 to anyof the directions 534, 536, 538 because the base station 502 did notreceive any response from the user equipment 514, 516, 518 in thoserespective directions.

FIG. 6 is a diagram showing resource element allocation 600 forsynchronization signals and physical broadcast channels. The allocation600 includes symbol 602, symbol 604, symbol 606, and symbol 608. Eachsymbol is a collection of resource elements that are communicated by oneor more transmission symbols (e.g., by one orthogonal frequency divisionmultiplexing (OFDM) symbol).

Each symbol 602, 604, 606, 608 is denoted by a value l (the lowercaseletter L), which may be enumerated 0, 1, 2, and 3. Each symbol 602, 604,606, 608 includes 288 resource elements. Each resource element isdenoted by a value k, which may be enumerated 0 to 287. A resourceelement in the allocation 600 can be identified by coordinates (k, l).For example, resource element (0, 0) is the bottom, left-most resourceelement, which happens to be in the symbol space for the symbol 602. Aresource element is the smallest unit of information transmission in theallocation 600, and a resource element is essentially a narrow slice offrequency at a narrow slice of time.

The allocation 600 maps each of the symbols 602, 604, 606, 608 to adifferent channel, where a channel is a group of resource elementstogether for a predefined purpose. The allocation 600 maps the symbol602 to a primary synchronization signal 612 (PSS), which mayalternatively be referred to as a primary synchronization channel(PSCH). The allocation 600 maps the symbol 606 to a secondarysynchronization signal 616 (SSS), which may alternatively be referred toas a secondary synchronization channel (SSCH). The allocation 600 mapsthe symbol 604 to a physical broadcast signal, which may alternativelybe referred to as a physical broadcast channel 614 (PBCH). Theallocation 600 additionally maps the symbol 608 to the physicalbroadcast channel 618 (PBCH).

The primary synchronization signal 612, secondary synchronization signal616, and physical broadcast channel 614, 618 may be signals transmittedby a base station to all user equipment in the base station's cell,regardless of whether the user equipment has established a connection tothe base station. In particular, the physical broadcast channel 614, 618may carry information that identifies the timing information (e.g., SFN,SS block index, etc.) used for user equipment timing determination,identifies how to decode other downlink transmission (e.g. RMSIscheduling information carried by PDCCH) from the base station, etc. Thephysical broadcast channel 618 may repeat substantially the sameinformation included in the physical broadcast channel 614. The primarysynchronization signal 612 and secondary synchronization signal 616 maycarry information that identify cell that pertains to the base stationas well as timing information for other downlink transmissions from thebase station.

As shown in FIG. 6 , the physical broadcast channel 614, 618 may use all288 resource elements of the symbols 604, 608 to which the physicalbroadcast channel 614, 618 is allocated. For example, all 288 resourceelements may carry information pertaining to the physical broadcastchannel 614, 618 (including system information and DMRS for PBCH). Asanother example, even if all 288 resource elements to do not carryinformation pertaining to the physical broadcast channel 614, 618, thephysical broadcast channel 614, 618 may include information insubstantially the full range of 288 resource elements, even if someresource elements in the range are not used.

On the other hand, the primary synchronization signal 612 and thesecondary synchronization signal 616 may not use all 288 resourceelements of the symbols 602, 606 to which the primary synchronizationsignal 612 and the secondary synchronization signal 616 are allocated,respectively. For example, the primary synchronization signal 612 mayonly map synchronization information to resource elements k=72 to 215 ofsymbol 602 (l=0). This may leave some resource elements of symbol 602(e.g., for l=0, k=0 to 71 and k=216 to 287) that do not carry anyinformation pertaining to the primary synchronization signal 612. Theseunused portions of the symbol 602 may thus be mapped to a first resource622 (showed with hatching). The first resource 622 may further includeportions of the symbol 606 which are not used by the secondarysynchronization signal 616.

In some embodiments, the first resource can be served as a non-scheduledphysical channel. In particular, the base station transmits informationwith fixed resource allocation, default modulation and coding scheme.Accordingly, no blind detection is needed for user equipment receivingsuch information. The first resource can also be defined as controlresource set/search space for downlink control information transmission.In the case, the first resource can carry one or more downlink controlinformation with different DCI format. The modulation and coding schemeof such downlink control information can also be changed. Accordingly,the UE will detect the target DCI with corresponding DCI format in thefirst resource. One or more following control information can share asame DCI format or define different DCI formats for each of them: pagingdownlink control information (paging DCI), paging reason categoryindication information, scheduling information of the remaining minimumsystem information, user equipment indication information, and pagingtransmission mode indication information.

In some embodiments, the paging indication as described previously(e.g., paging indication 424, 542) may be mapped to the first resource622. In addition, the paging indication may be carried on the firstresource 622 that uses the same antenna port as the physical broadcastchannel 614, 618. That is, the information contained in the pagingindication (e.g., identifying a user equipment or a group of userequipment that should respond to the paging indication) may betransmitted using the resource elements of the first resource 622. Thismapping may be beneficial for various reasons. For example, the firstresource 622 may otherwise not be put to use by the allocation 600 andthe base station that transmits according to the allocation 600. Asanother example, the symbols 602, 604, 606, 608 containing the primarysynchronization signal 612, the secondary synchronization signal 616,and the physical broadcast channel 614, 618 may be symbols that aretransmitted frequently and on all antenna ports (e.g., due to theimportance of the information in those symbols for decoding otherdownlink transmissions). As such, the first resource 622 may be anadvantageous group of resource elements in which to transmit the pagingindication as being an efficient use of existing resources that arealready being transmitted to all antenna ports.

As used herein, mapping may refer to any of a variety of activitiesrelated to providing specific information in a specific one or moreresource elements. For example, mapping may include transmittingspecific information in a specific one or more resource elements. Asanother example, mapping may including reserving a specific one or moreresource elements for specific information. As another example, mappingmay including allocating a specific one or more resource elements tospecific information. As another example, mapping may include storingspecific information in a buffer or other memory in order to transmitthe specific information in a specific one or more resource elements.

In some embodiments, the first resource may be described in other ways.For example, it can be observed that the enumeration of resourceelements k=0 to 287 is an enumeration in the frequency domain. Thus,because the primary synchronization signal 612 and secondarysynchronization signal 616 occupy a smaller range of resource elementsthan does the physical broadcast channel 614, 618, it can be observedthat the primary synchronization signal 612 and secondarysynchronization signal 616 occupy a narrower bandwidth than does thephysical broadcast channel 614, 618. Thus the first resource 622 may bedescribed as being in a symbol 602, 606 allocated to the primarysynchronization signal 612 and/or secondary synchronization signal 616,but outside the bandwidth of the primary synchronization signal 612and/or secondary synchronization signal 616, and inside the bandwidth ofthe physical broadcast channel 614, 618.

FIG. 7 is a diagram showing resource element allocation 700 tosynchronization and broadcast channels. The allocation 700 may beprovided substantially as described with respect to the allocation 600,with like reference numerals denoting like items.

The allocation 700 shows further detail on how the resource elements ofthe symbols 604 and 608 may be mapped by the physical broadcast channel614, 618. In particular, the physical broadcast channel 614, 618 may usethe resource elements in the ranges k=0 to 71 and k=216 to 287 in a waythat is different from the use of the resource elements in the rangek=72 to k=215. These outside ranges may be referred to collectively as asecond resource 724. In addition, the paging indication carried by thefirst resource 622 that uses the same antenna port as the physicalbroadcast channel 614, 618. As such, demodulation reference signals ofthe second resource 724 can be used for demodulating the pagingindication transmitted in the first resource 622.

The second resource 724 may include a physical broadcast channelresource block 730. In this context, a resource block refers to acontinuous resource element (e.g., 12 continuous resource elements). Theresource block 730 may include a mixture of demodulation referencesignals 732 and PBCH resource elements. The demodulation referencesignals 732 may be signals that the user equipment uses to determine howto demodulate the remainder of the resource elements in the symbols inwhich they occur (i.e., the symbols 604, 608). As shown, the resourceblock 730 and the second resource 724 may contain a 1 to 4 ratio ofdemodulation reference signals 732 to all of the resource elements.

In some embodiments, the first resource 622 may be mapped to a pagingindication without also mapping a demodulation reference signal to thefirst resource 622. This may allow one or more continuous resources ofone or more resource elements in the first resource 622 to be used totransmit the paging indication. Here a continuous resource may refer toan uninterrupted range of resource elements (e.g., k=216 to 287 in thesymbol 602). This may be beneficial as allowing a simpler mapping andtransmission scheme for the paging indication. This may also bebeneficial for improving the efficiency of resource element usage.

At the same time, it may be necessary to have a demodulation referencesignal in order for the user equipment to demodulate the pagingindication transmitted in the first resource 622. As such, ademodulation reference signal 732 may be mapped to the second resource724. And, the user equipment may use the demodulation reference signal732 form the second resource 724 in order to demodulate the pagingindication transmitted in the first resource 622.

It may be advantageous to provide the demodulation reference signal 732in a the second resource 724 of a symbol that is adjacent to the symbolin which the first resource 622 is located carrying the pagingindication. Here adjacency refers to adjacency of symbols (e.g., thesymbols 604 is adjacent to the symbols 602 and 606 but not to the symbol608). This approach may be advantageous as allowing the immediatedemodulation of the paging indication, which in turn may lead to moreefficient operation of the user equipment and subsequent paging process.

As with the first resource 622, the second resource 724 may be describedin terms of its bandwidth location. For example, the second resource 724may be described as being in a symbol 604, 608 allocated to the physicalbroadcast channel 614, outside the bandwidth of the primarysynchronization signal 612 and/or secondary synchronization signal 616,and inside the bandwidth of the physical broadcast channel 614, 618.Notwithstanding the fact that FIG. 7 illustrates the second resource 724as a separate block from the physical broadcast channel 614, 618, itshould be understood that the second resource 724 may be considered apart of the physical broadcast channel 614, 618.

FIG. 8 is a diagram showing resource element allocation 800 tosynchronization and broadcast channels. The allocation 800 may beprovided substantially as described with respect to the allocations 600,700, with like reference numerals denoting like items. However, theallocation 800 illustrates a situation where the enumerations ofresource elements (using k and l) and symbols (using l) may be differentthan that described for the allocations 600, 700.

When the subcarriers are uniformly numbered within the bandwidth part(BWP) (or minimum system bandwidth) of the synchronizationsignal/physical broadcast channel block, k₀ may be introduced. In suchinstances, the first resource 622 includes resource element (k, l);where k represents the frequency domain index, that is, the subcarriernumber within the bandwidth part, k ranges from {k₀, k₀+1, . . . ,k₀+71, k₀+216, k₀+217, . . . , k₀+287}, where k₀ is the value of thesubcarrier offset between the synchronization signal/physical broadcastchannel block starting subcarrier and bandwidth part startingsubcarrier. Here l represents the time domain index, that is, the symbolindex in the slot, l={l₀+0, l₀+2}, where l₀ is the value of the symboloffset between the synchronous signal/physical broadcast channel blockstarting symbol and the slot starting symbol.

As referred to herein, the minimum system bandwidth means the maximumsystem bandwidth supported by the system or user equipment with minimumcapacity. All of the system components and user equipment can completetransmission and reception within minimum system bandwidth.

FIG. 9 is a diagram showing resource element allocation 900 tosynchronization and broadcast channels. The allocation 900 may beprovided substantially as described with respect to the allocations 600,700, 800, with like reference numerals denoting like items. However, theallocation 900 illustrates a situation where the mapping of resourceelements to the first resource 622 may be different than that describedfor the allocations 600, 700, 800.

In the time domain direction, the first resource 622 is mapped to thesymbols 602, 606 where the primary synchronization signal 612 and thesecondary synchronization signal 616 are located. In the frequencydomain direction, the first resource 622 is mapped outside the bandwidthof the primary synchronization signal 612 and the secondarysynchronization signal 616 but within the resource elements of thebandwidth part/the minimum system bandwidth. The first resource 622includes the resource element (k, l); where k represents the frequencydomain index, that is, the subcarrier number within the bandwidthpart/the minimum system bandwidth, k ranges from {0, 1, . . . , k₀+71,k₀+216, k₀+217, . . . , K}, where k₀ is the value of subcarrier offsetbetween the synchronization signal/physical broadcast channel blockstarting subcarrier and bandwidth part starting subcarrier, K representsthe maximum subcarrier number of the bandwidth part/the minimum systembandwidth. Here l represents the time domain index, that is, the symbolindex in the slot, l={l₀+0, l₀+2}, where l₀ is the value of symboloffset between the synchronization signal/physical broadcast channelblock starting symbol and the slot starting symbol.

In such embodiments, additional demodulation reference signals may beintroduced for part of the first resource 622. In particular, additionaldemodulation reference signals may be included in the symbols for theprimary synchronization signal 612 and the secondary synchronizationsignal 616 but outside the bandwidth of the physical broadcast channel614, 618, such as with k ranges from {0, 1, . . . , k₀−1, k₀+288,k₀+289, . . . , K} for both symbols l={l₀+0, l₀+2}.

FIG. 10 is a diagram showing resource element allocation 1000 tosynchronization and broadcast channels. The allocation 1000 may beprovided substantially as described with respect to the allocations 600,700, 800, 900, with like reference numerals denoting like items.However, the allocation 1000 illustrates a situation where the mappingof resource elements to the first resource 622 may be different thanthat described for the allocations 600, 700, 800, 900.

In the time domain, the first resource 622 is mapped to the symbols 602,606 where the primary synchronization signal 612 and the secondarysynchronization signal 616 are located. The first resource 622 is alsomapped to the symbols 604, 608 where the physical broadcast channel 614,618 are located. In the frequency domain direction, for symbols wherethe primary synchronization signal 612 and the secondary synchronizationsignal 616 are located, the first resource 622 is mapped outside thebandwidth of the primary synchronization signal 612 and the secondarysynchronization signal 616 but within the resource elements of thebandwidth part/the minimum system bandwidth. The first resource 622includes the resource element (k, l); where k represents the frequencydomain index, that is, the subcarrier number within the bandwidthpart/the minimum system bandwidth, k ranges from {0, 1, . . . , k₀+71,k₀+216, k₀+217, . . . , K}, where k₀ is the value of the subcarrieroffset between the synchronization signal/physical broadcast channelblock starting subcarrier and bandwidth part starting subcarrier, Krepresents the maximum subcarrier number of the bandwidth part/theminimum system bandwidth. Here 1 represents the time domain index, thatis, the symbol index in the slot, l={l₀+0, l₀+2}, where l₀ is the valueof symbol offset between the synchronous signal/physical broadcastchannel block starting symbol and the slot starting symbol.

For the symbols 604, 608 where the physical broadcast channel 614, 618is located, the first resource 622 is mapped outside the bandwidth ofthe physical broadcast channel 614, 618 but within the resource elementsof the bandwidth part/the minimum system bandwidth. The first resource622 includes the resource element (k, l); where k represents thefrequency domain index, that is, the subcarrier number within thebandwidth part/the minimum system bandwidth, k ranges from {0, 1, . . ., k₀−1, k₀+288, k₀+289, . . . , K}, where k₀ is the value of subcarrieroffset between the synchronization signal/physical broadcast channelblock starting subcarrier and bandwidth part starting subcarrier, Krepresents the maximum subcarrier number of the bandwidth part or theminimum system bandwidth. Here l represents the time domain index, thatis, the symbol index in the slot, l={l₀+1, l₀+3}, where l₀ is the valueof symbol offset between the synchronous signal/physical broadcastchannel block starting symbol and the slot starting symbol.

In such embodiments, additional demodulation reference signals may beintroduced for part of the first resource 622. In particular, additionaldemodulation reference signals may be included in the symbols for theprimary synchronization signal 612, the secondary synchronization signal616, and the physical broadcast channel 614, 618, but outside thebandwidth of the physical broadcast channel 614, 618, k ranges from {0,1, . . . , k₀−1, k₀+288, k₀+289, . . . , K} for all of the symbolsl={l₀+0, l₀+1, l₀+2, l₀+3}.

In accordance with various embodiments described herein, the firstresource can also carry various information. These include one or moreof: paging downlink control information (paging DCI), paging reasoncategory indication information, scheduling information of the remainingminimum system information, user equipment indication information andpaging transmission mode indication information.

In various embodiments, there are two major categories reasons forpaging. First, specific paging, and, second, public paging.

With specific paging, the base station is seeking to page a specificuser equipment, such as when a user equipment is being called. In suchsituations, the base station may transmit paging downlink controlinformation as part of the paging indication. The paging downlinkcontrol information may include scheduling information for a pagingmessage, and the paging message may include identification informationof the called user equipment (such as the user equipment's SAE temporarymobile subscriber identity, S-TMSI). Upon receiving the paging message,the user equipment determines that it is being paged and access thenetwork to perform appropriate communications.

With public paging, the base station is seeking to page all userequipment within the base station's cell. Public paging may be brokendown further into system message changing indication, early warninginformation (such as an earthquake and tsunami warning system (ETWS)notification), a commercial mobile alarm service (CMAS) notification,extended access barring (EAB) parameter changes, etc. Each of these isused to indicate that system information has changed, as opposed to aspecific paging of a specific user equipment. The system changeinformation can further include: remaining minimum system informationand other system information, wherein the remaining minimum systeminformation is the remaining system information of the minimum systeminformation other than the main system information. The minimum systeminformation is required system information during the initial accessprocess of the user equipment. The main system information is systeminformation carried on the physical broadcast channel. The other systeminformation is system information of all system information other thanthe minimum system information.

In some embodiments, the first resource carries (e.g., as included inthe paging indication) paging downlink control information. When thepaging indication includes paging downlink control information, thesystem may transmit the paging indication in a sweeping mode, therebytransmitting the paging indication on all antenna ports and thus in allbeam directions. Such embodiments may include both specific pagingreasons and public paging reasons. In such situations, the pagingindication including the paging downlink control information is mappedto the a first resource as described previously (e.g., the firstresource 622).

The paging downlink control information can include schedulinginformation for the paging message. The scheduling information mayindicate the transmission mode of the subsequent paging message, theresource allocation, and the like. In such situation, the paging messagemay also be sent in a sweeping mode on all antenna ports. Thetransmission resource of the paging message may be frequency-multiplexedwith the synchronization signal/physical broadcast channel block in thesame symbol, or another round of sweeping structure may be introduced.

In some embodiments, the first resource carries (e.g., as included inthe paging indication) paging reason category indication information.The paging reason category indication information may be used toindicate a reason for which a paging indication is being transmitted.When the paging indication includes paging reason category indicationinformation, the system may transmit the paging indication in a sweepingmode, thereby transmitting the paging indication on all antenna portsand thus in all beam directions.

For the public paging reason, the type of public paging may be indicatedby a bitmap. Further consideration may be given to refine the systeminformation update instructions, such as by classifying the update asRMSI (remaining minimum system information) update or other systeminformation updates. The two updates may be further classified, dividedinto RMSI subclasses and other SI subclasses to specify which subclassesare updated.

FIGS. 11A, 11B, 11C, and 11D are diagram showing exemplary datastructures 1110, 1120, 1130, and 1140, respectively, for transmittingpaging reason category indication information. In some embodiments, oneor more of the data structures 1110, 1120, 1130, 1140 may be transmittedas part of a paging indication.

The data structure 1110 includes the following: a system informationupdate indication field, which contains one bit to indicate whether theRMSI is updated and one bit to indicate whether the other SI is updated.For example, a value of 0 can indicate no update, while a value of 1 canindicate that an update has occurred. The data structure 1110 mayinclude additional bits to indicate a cause of the page for a reasonother than the system information update (e.g., an early warningnotification).

The data structure 1120 includes the following: a system informationupdate indication field, which contains one bit to indicate whether thesystem information is updated and one bit to indicate whether only otherSI is updated. For example, a value of 0 can indicate no update, while avalue of 1 can indicate that an update has occurred. The data structure1110 may include additional bits to indicate a cause of the page for areason other than the system information update (e.g., an early warningnotification).

The data structure 1130 includes the following: a system informationupdate indication field, which contains N bits to indicate whether eachof N subclasses of RMSI information is updated and M bits to indicatewhether each of M subclasses of other SI information is updated. Forexample, a value of 0 can indicate no update, while a value of 1 canindicate that an update has occurred. In such embodiments, the RMSI andother SI information can be divided into subclasses as described above,and one bit of the system information update indication field cancorrespond to whether or not each subclass is updated. The datastructure 1110 may include additional bits to indicate a cause of thepage for a reason other than the system information update (e.g., anearly warning notification).

The data structure 1140 includes the following: a system informationupdate indication field, which contains one bit to indicate whether thesystem information is updated and M bits to indicate whether each of Msubclasses of other SI information is updated. For example, a value of 0can indicate no update, while a value of 1 can indicate that an updatehas occurred. In such embodiments, the other SI information can bedivided into subclasses as described above, and one bit of the systeminformation update indication field can correspond to whether or noteach subclass is updated. The data structure 1110 may include additionalbits to indicate a cause of the page fora reason other than the systeminformation update (e.g., an early warning notification).

In some embodiments, the first resource carries (e.g., as included inthe paging indication) scheduling information of the remaining minimumsystem information (RMSI DCI). When the paging indication includesscheduling information of the remaining minimum system information, thesystem may transmit the paging indication in a sweeping mode, therebytransmitting the paging indication on all antenna ports and thus in allbeam directions. Such embodiments may include both specific pagingreasons and public paging reasons. In such situations, the pagingindication including the scheduling information of the remaining minimumsystem information is mapped to the a first resource as describedpreviously (e.g., the first resource 622).

In some embodiments, the first resource carries (e.g., as included inthe paging indication) user equipment indication information. The userequipment indication information may be used for paging a particularuser equipment. When the paging indication includes user equipmentindication information, the system may transmit the paging indication ina sweeping mode, thereby transmitting the paging indication on allantenna ports and thus in all beam directions.

The user equipment indication information may contain a plurality ofbits. In some embodiments, each bit of the plurality of bits maycorrespond to a group of user equipment. The relationship between eachbit and a user equipment can be predefined, such as being based on theterminal identifier. As such, the groups of user equipment correspondingto each bit may be formed in a predefined and arbitrary fashion. Thisapproach may be beneficial as allowing the base station to page a groupof terminals under the same paging occasion.

FIG. 12 is a diagram of an exemplary data structure 1200 fortransmitting user equipment indication information. As shown, the datastructure 1200 contains eight bits. With such a data structure, all userequipment can be sorted into one of eight groups. For example, each userequipment's TMSI can be divided by eight, and the remainder value candetermine to which group the user equipment belongs. Other techniquesare possible. When the data structure 1200 is transmitted as part of thepaging indication. A user equipment can check the value for its group(e.g., check bit 3 for a user equipment in group 3). If the bit value is0, then the user equipment can determine that no response is necessary.If the bit value is 1, then the user equipment can determine thatfurther paging is necessary, and thus provide an appropriate response.

An example can be given of how the user equipment indication informationmay work. The base station may set a bit to “1” for a group of userequipment to which a user equipment belongs that the base station willattempt to page (i.e., set the bit for the group of the user equipmentthat is being called). When each user equipment in the indicated groupreceives the user equipment indication information, each such userequipment can respond by transmitting an indication of the beamdirection in which it is located or the antenna port by which the basestation transmits. The base station may then subsequently send pagingdownlink control information and/or a paging message in the indicatedbeam direction or on the indicated antenna port. This subsequenttransmission of the paging downlink control information and/or pagingmessage can indicate which user equipment is/are being paged fromamongst the group of user equipment.

In some embodiments, the first resource carries (e.g., as included inthe paging indication) paging transmission mode indication information.The paging transmission mode indication information may be used toidentify a mode by which a paging message will be transmitted, asdiscussed further below. When the paging indication includes pagingtransmission mode indication information, the system may transmit thepaging indication in a sweeping mode, thereby transmitting the pagingindication on all antenna ports and thus in all beam directions.

The paging transmission mode indication information may indicate thepaging transmission mode to the groups of user equipment using, forexample, by transmitting user equipment indication information asdescribed above along with separate bits for each group for the pagingtransmission mode indication information (e.g., one to two bits for eachgroup). One benefit of indicating paging transmission mode by groups isthat it enables different groups of terminals to use different pagingtransmission modes. Thus even with two user equipment that belong to twodifferent user equipment groups, both user equipment groups can beindicated in a single paging indication, and additionally each group canhave a separate paging transmission mode indicated in the same pagingindication. However, in some embodiments, a single paging transmissionmode indicator can be used for all user equipment groups in a pagingindication, in which case all user equipment groups would use the sameindicated paging transmission mode.

In some embodiments three paging transmission modes may be available.

In mode 1, the base station transmits the paging indication and receivesa response in a random access request preamble sequence. The basestation then transmits the paging downlink control information and/orpaging message in the downlink antenna port indicated by the randomaccess preamble sequence.

In mode 2, the base station transmits the paging indication and receivesa response in a random access request preamble sequence. The basestation then transmits a random access response in a downlink antennaport indicated by the random access preamble sequence, with the randomaccess response including the identifier (e.g., S-TMSI) of the userequipment being paged. In this mode, the base station may further acceptthe re-random access of the paged user equipment.

In mode 3, the base station transmits the paging indication and receivesa response in a random access request preamble sequence. The basestation then transmits a random access response in a downlink antennaport indicated by the random access preamble sequence, with the randomaccess response including: the identifier (e.g., S-TMSI) of the userequipment being paged, a timing advance command, and uplink grantinformation. The base station can then return a contention resolutionmessage to the user equipment that is successfully accessed by the userequipment being paged.

In some embodiments, the paging indication can include a combination ofthe other elements previously described. For example, a pagingindication can contain a user equipment indication information andpaging transmission mode indication information. Other combinations ofinformation in the paging indication are possible in accordance withvarious embodiments of the present disclosure.

FIG. 13 is a diagram of a data structure 1300 for transmitting userequipment indication information and paging reason category indicationinformation. The data structure 1300 includes eight bits fortransmitting user equipment indication information (e.g., as describedwith respect to the data structure 1200), seven bits for transmittingpaging reason category indication information (e.g., as described withrespect to the data structures 1310, 1320, 1330, 1340), and sixteen bitsfor a cyclic redundancy check. In some embodiments, the bits of thecyclic redundancy check may be scrambled using the P-RNTI. In variousembodiments, the number of bits allocated to each type of informationcan be varied, and the above number of bits for each type of informationis given for exemplary purposes only.

The information carried on the first resource may be pre-defined by thesystem or may be notified to the user equipment by signaling. Forexample, the base station may indicate in the PBCH what information iscontained in the current first resource. As another example, differenttypes of paging indications may be defined which include differentinformation, and the base station may indicate in the PBCH the currenttype of information carried by the first resource. Alternatively, theuser equipment may determine the current type of information carried bythe first resource by way of a blind detection. For example, differenttypes of first resources with different CRC masks, or differentscrambling codes for the encoded information bits, etc. may be used. Theuser equipment may blindly detect the current CRC code, or a differentscrambling code for the encoded information bits in order to determinethe current type of information carried by the first resource.

FIG. 14 is a sequence diagram of a process 1400 for paging transmission.The process 1400 may be referred to herein as mode 1. The process 1400involves a base station 1402 (e.g., as described for base station 102,302, 402, 502, wireless communication apparatus 200) and user equipment1412, 1414, 1416, 1418 (e.g., as described for user equipment 106, 312,404, 512, wireless communication apparatus 200). In some embodiments,the user equipment 1412, 1414, 1416, 1418 belong to a same pagingoccasion (PO). Paging occasion is defined as time resource correspondingto a sweeping structure for paging transmission in different antennaports. User equipments can be divided into different POs basing on theuser equipment identification. In paging trigger mode, the time resourcecorresponding to a sweeping structure used for paging indicationstransmission can be defined as PO. In some embodiments, methods aredescribed under the case that user equipments belong to a same PO. Inthe present example, the base station 1402 may have antennas and antennaports that correspond to 20 beam directions.

The user equipment 1412, 1414, 1416, 1418 may each belong to userequipment groups. For example, the user equipment 1412, 1414, 1416 maybelong to user group 4, while the user equipment 1418 may belong to usergroup 5.

The user equipment 1412, 1414, 1416, 1418 may be present in beamdirections of the cell serviced by the base station 1402. For example,the user equipment 1412 may be present in beam direction 3 and servicedby antenna port 3. The user equipment 1414 may be present in a beamdirection 6 and serviced by antenna port 6. The user equipment 1416 maybe present in a beam direction 8 and serviced by antenna port 8. Theuser equipment 1418 may be present in a beam direction 9 and serviced byantenna port 9.

Prior to beginning the process 1400, the base station 1402 may determinethat it is necessary to page the user equipment 1412 and the userequipment 1414 (e.g., the network notifies the base station 1402 ofincoming calls for the user equipment 1412, 1414)

The base station 1402 determines a user equipment group 1422. The basestation 1402 may determine the user equipment group 1422 by determiningto which groups the user equipment that need to be paged belong. In thisexample, the base station 1402 would determine the user equipment group4, because both of the user equipment that need to be paged (i.e., theuser equipment 1412, 1414) belong to the user equipment group 4.

The base station transmits paging indication 1424. The base station 1402may transmit the paging indication 1424 on all antenna ports in asweeping fashion. As such, all user equipment present in the cellserviced by the base station 1402 (or at least all such user equipmentthat are awake during this paging occasion), including each of the userequipment 1412, 1414, 1416, 1418, will receive the paging indication1424.

The paging indication 1424 may include user equipment indicationinformation. For example, the paging indication may contain eight bits(e.g., XXXXXXXX as described with respect to the data structure 1200)that identify which user equipment groups are being paged. In thepresent example, the user equipment indication information may be00001000 to indicate that only the user equipment group 4 is beingpaged.

The paging indication 1424 may further include paging transmission modeindication information to indicate a paging transmission mode that thebase station will use. Because the base station 1402 is using mode 1,the paging transmission mode indication information may indicate a valueof 1 (e.g., 01).

In some embodiments, the paging indication 1424 may include furtherinformation. For example, the paging indication 1424 may include pagingdownlink control information will the CRC scrambled using the P-RNTI asa mask. The paging indication may contain scheduling information for thepaging message that will be transmitted.

When the user equipment 1412, 1414, 1416, 1418 receive the pagingindication 1424, each can determine whether or not it is in the userequipment group 1422 being paged. The user equipment 1418 determinesthat it is not in the user equipment group 1422 being paged (because bit5 of the user equipment indication information is set to 0), so the userequipment 1418 takes no further action (e.g., returns to idle mode).

Each of the user equipment 1412, 1414, 1416 determine that they are inthe user equipment group 1422 being paged (because bit 4 of the userequipment indication information is set to 1), so each of the userequipment 1412, 1414, 1416 prepare to send a response 1426 to the pagingindication. The response 1426 from each of the user equipment 1412,1414, 1416 may include an indication of the antenna port in which theeach user equipment is located. For example, each of the user equipment1412, 1414, 1416 may select a resource for transmission of the response1426 that corresponds to the antenna port where that equipment islocated. For example, the user equipment 1412 may transmit the response1426 on a resource corresponding to antenna port 3. The user equipment1414 may transmit the response 1426 on a resource corresponding toantenna port 6. The user equipment 1416 may transmit the response 1426on a resource corresponding to antenna port 8.

In some embodiments, the user equipment 1412, 1414, 1416 may transmitthe response 1426 as a preamble on a random access channel (RACH). Insome situations, this preamble may be part of what would otherwise becalled a “request” on the random access channel. But in the presentexample, the user equipment 1412, 1414, 1416 may use the random accesschannel “request” in order to send the response 1426 to the base station1402.

In some embodiments, the base station 1402 may send a response 1428 toeach of the received responses 1426. The response 1428 may serve tonotify each of the user equipment 1412, 1414, 1416 that the response1426 was in fact received by the base station 1402. In some embodiments,the response 1428 may be transmitted on the random access channel as arandom access response (RAR) message in response to the preamblecontaining the response 1426. In such embodiments, the RAR of theresponse 1428 may only contain a random access preamble identification(RAPID) that indicated the user equipment whose preamble the current RARcorresponds to. In some embodiments, the base station may omittransmission of the response 1428.

The base station 1402 transmits a paging downlink control informationand/or paging message 1430. The base station 1402 may transmit thepaging message 1430 using a standard paging channel (e.g., PCCH/PCH).Based on the responses 1426, the base station 1402 can determine asubset of the total beam directions or antenna ports into which thepaging message 1430 should be transmitted. In the present example, thebase station 1402 determines that the paging message 1430 only needs tobe transmitted to beam directions/antenna ports 3, 6, and 8 of the 20total beam directions/antenna ports, because all members of the userequipment group 1422 being paged (i.e., user equipment group 4) are inthose three directions. As a result, the base station 1402 transmits thepaging message 1430 only to the antenna ports for the beam directions 3,6, and 8. Because the user equipment 1412, 1414, 1416 are each in one ofthe directions to which the paging message 1430 was transmitted, each ofthe user equipment 1412, 1414, 1416 will receive the paging message1430.

In some embodiments, the base station 1402 may additionally send relatedinformation, such as paging downlink control information to theidentified beam directions/antenna ports (i.e., directions 3, 6, 8). Insome embodiments, the base station 1402 may transmit the paging message1430 during the next paging occasion after the transmission of thepaging indication 1424 that corresponds to the user equipment beingpaged. Alternatively, the paging message 1430 may be transmitted in apredefined time-frequency resource.

In some embodiments, the paging message 1430 may contain an identifierfor each user equipment actually being paged. In the present example,the paging message 1430 would contain identifiers (e.g., S-TMSI) for theuser equipment 1412 and the user equipment 1414. After receiving thepaging message 1430, each of the user equipment 1412, 1414, 1416 candetermine if it was being paged. The user equipment 1416 would determinethat it is not being paged, because its identifier was not included inthe paging message 1430. Whereas the user equipment 1412, 1414 wouldeach determine that it was being paged, because its identifier wasincluded in the paging message 1430. User equipment that determine thatthey are being paged may perform a random access procedure on the randomaccess channel in order to access the network in accordance with thepaging message 1430.

FIG. 15 is a sequence diagram of a process 1500 for paging transmission.The process 1500 may be referred to herein as mode 2. The process 1500involves the base station 1402 and the user equipment 1412, 1414, 1416,1418 (e.g., as described for user equipment 106, 312, 404, 512, wirelesscommunication apparatus 200).

As described previously, the base station 1402 may have antennas andantenna ports that correspond to 20 beam directions. The user equipment1412, 1414, 1416 may belong to user group 4, while the user equipment1418 may belong to user group 5. The user equipment 1412 may be presentin beam direction 3 and serviced by antenna port 3. The user equipment1414 may be present in a beam direction 6 and serviced by antenna port6. The user equipment 1416 may be present in a beam direction 8 andserviced by antenna port 8. The user equipment 1418 may be present inabeam 9 direction and serviced by antenna port 9.

Prior to beginning the process 1500, the base station 1402 may determinethat it is necessary to page the user equipment 1412 and the userequipment 1414 (e.g., the network notifies the base station 1402 ofincoming calls for the user equipment 1412, 1414).

The base station 1402 determines a user equipment group 1522. The basestation 1402 may determine the user equipment group 1522 by determiningto which groups the user equipment that need to be paged belong. In thisexample, the base station 1402 would determine the user equipment group4, because both of the user equipment that need to be paged (i.e., theuser equipment 1412, 1414) belong to the user equipment group 4.

The base station transmits paging indication 1524. The base station 1402may transmit the paging indication 1524 on all antenna ports for allbeam directions in a sweeping fashion. As such, all user equipmentpresent in the cell serviced by the base station 1402 (or at least allsuch user equipment that are awake during this paging occasion),including each of the user equipment 1412, 1414, 1416, 1418, willreceive the paging indication 1524.

The paging indication 1524 may include user equipment indicationinformation. For example, the paging indication may contain eight bits(e.g., XXXXXXXX as described with respect to the data structure 1200)that identify which user equipment groups are being paged. In thepresent example, the user equipment indication information may be00001000 to indicate that only the user equipment group 4 is beingpaged.

The paging indication 1524 may further include paging transmission modeindication information to indicate a paging transmission mode that thebase station will use. Because the base station 1402 is using mode 2,the paging transmission mode indication information may indicate a valueof 2 (e.g., 10).

In some embodiments, the paging indication 1524 may include furtherinformation. For example, the paging indication 1524 may include pagingdownlink control information will the CRC scrambled using the P-RNTI asa mask. The paging indication may contain scheduling information for thepaging message that will be transmitted.

When the user equipment 1412, 1414, 1416, 1418 receive the pagingindication 1524, each can determine whether or not it is in the userequipment group 1522 being paged. The user equipment 1418 determinesthat it is not in the user equipment group 1522 being paged (because bit5 of the user equipment indication information is set to 0), so the userequipment 1418 takes no further action (e.g., returns to idle mode).

Each of the user equipment 1412, 1414, 1416 determine that they are inthe user equipment group 1522 being paged (because bit 4 of the userequipment indication information is set to 1), so each of the userequipment 1412, 1414, 1416 prepare to send a response 1526 to the pagingindication. The response 1526 from each of the user equipment 1412,1414, 1416 may include an indication of the antenna port in which eachof the user equipment 1412, 1414, 1416 is located. For example, each ofthe user equipment 1412, 1414, 1416 may select a resource fortransmission of the response 1526 that corresponds to the antenna portwhere that user equipment is located. For example, the user equipment1412 may transmit the response 1526 on a resource for antenna port 3.The user equipment 1414 may transmit the response 1526 on a resource forantenna port 6. The user equipment 1416 may transmit the response 1526on a resource for antenna port 8.

In some embodiments, the user equipment 1412, 1414, 1416 may transmitthe response 1526 as a preamble on a random access channel (RACH). Insome situations, this preamble may be part of what would otherwise becalled a “request” on the random access channel. But in the presentexample, the user equipment 1412, 1414, 1416 may use the random accesschannel “request” in order to send the response 1526 to the base station1402.

The base station 1402 transmits a response 1528. The base station 1402may transmit the response 1528 as a random access response (RAR) messageon the same random access channel on which it receive the response 1526.The response 1528 may contain the paging message that the base station1402 is attempting to deliver to the user equipment being paged. Thatis, mode 1 and mode 2 differ, at least in that mode 1 transmits thepaging message on a standard paging channel (e.g., PCCH/PCH) whereasmode 2 transmits the paging message as part of a response on the randomaccess channel (RACH).

Based on the responses 1526, the base station 1402 can determine asubset of the total beam directions/antenna ports into which theresponse 1528 should be transmitted. In the present example, the basestation 1402 determines that the response 1528 only needs to betransmitted to beam directions/antenna ports 3, 6, and 8 of the 20 totalbeam directions/antenna ports, because all members of the user equipmentgroup 1522 being paged (i.e., user equipment group 4) are in those threedirections. As a result, the base station 1402 transmits the response1528 only to the antenna ports for the beam directions 3, 6, and 8.Because the user equipment 1412, 1414, 1416 are each in one of thedirections to which the response 1528 was transmitted, each of the userequipment 1412, 1414, 1416 will receive the response 1528.

In some embodiments, the response 1528 may contain an identifier foreach user equipment actually being paged. In the present example, theresponse 1528 would contain identifiers (e.g., S-TMSI) for the userequipment 1412 and the user equipment 1414. After receiving the response1528, each of the user equipment 1412, 1414, 1416 can determine if itwas being paged. The user equipment 1416 would determine that it is notbeing paged, because its identifier was not included in the response1528. Whereas the user equipment 1412, 1414 would each determine that itwas being paged, because its identifier was included in the response1528. User equipment that determine that they are being paged mayperform a random access procedure on the random access channel in orderto access the network in accordance with the response 1530.

In the process 1500, the receiving configuration of the RAR of theresponse 1528 may be configured to the user equipment in the remainingminimized system information (RMSI). The user equipment can detect theRAR of the response 1528 in a plurality of physical downlink controlchannels within the corresponding RAR window. The RAR schedulinginformation can scramble the CRC of the downlink control informationwith the RA-RNTI as a mask. The RAR of the response 1528 also caninclude the corresponding random access preamble identification (RAPID)to indicate the user equipment to which preamble the RAR of the response1528 corresponds. The RAR of the response 1528 does not need to includetiming advance indication and uplink authorization information.

FIG. 16 is a sequence diagram of a process 1600 for paging transmission.The process 1600 may be referred to herein as mode 3. The process 1600involves the base station 1402 and the user equipment 1412, 1414, 1416,1418 (e.g., as described for user equipment 106, 312, 404, 512, wirelesscommunication apparatus 200).

As described previously, the base station 1402 may have antennas andantenna ports that correspond to 20 beam directions. The user equipment1412, 1414, 1416 may belong to user group 4, while the user equipment1418 may belong to user group 5. The user equipment 1412 may be presentin beam direction 3 and service by antenna port 3. The user equipment1414 may be present in a beam direction 6 and service by antenna port 6.The user equipment 1416 may be present in a beam direction 8 and serviceby antenna port 8. The user equipment 1418 may be present in abeamdirection 9 and service by antenna port 9.

Prior to beginning the process 1600, the base station 1402 may determinethat it is necessary to page the user equipment 1412 and the userequipment 1414 (e.g., the network notifies the base station 1402 ofincoming calls for the user equipment 1412, 1414).

The base station 1402 determines a user equipment group 1622. The basestation 1402 may determine the user equipment group 1622 by determiningto which groups the user equipment that need to be paged belong. In thisexample, the base station 1402 would determine the user equipment group4, because both of the user equipment that need to be paged (i.e., theuser equipment 1412, 1414) belong to the user equipment group 4.

The base station transmits paging indication 1624. The base station 1402may transmit the paging indication 1624 on all antenna ports for allbeam directions in a sweeping fashion. As such, all user equipmentpresent in the cell serviced by the base station 1402 (or at least allsuch user equipment that are awake during this paging occasion),including each of the user equipment 1412, 1414, 1416, 1418, willreceive the paging indication 1624.

The paging indication 1624 may include user equipment indicationinformation. For example, the paging indication may contain eight bits(e.g., XXXXXXXX as described with respect to the data structure 1200)that identify which user equipment groups are being paged. In thepresent example, the user equipment indication information may be00001000 to indicate that only the user equipment group 4 is beingpaged.

The paging indication 1624 may further include paging transmission modeindication information to indicate a paging transmission mode that thebase station will use. Because the base station 1402 is using mode 3,the paging transmission mode indication information may indicate a valueof 3 (e.g., 11).

In some embodiments, the paging indication 1624 may include furtherinformation. For example, the paging indication 1624 may include pagingdownlink control information will the CRC scrambled using the P-RNTI asa mask. The paging indication may contain scheduling information for thepaging message that will be transmitted.

When the user equipment 1412, 1414, 1416, 1418 receive the pagingindication 1624, each can determine whether or not it is in the userequipment group 1622 being paged. The user equipment 1418 determinesthat it is not in the user equipment group 1622 being paged (because bit5 of the user equipment indication information is set to 0), so the userequipment 1418 takes no further action (e.g., returns to idle mode).

Each of the user equipment 1412, 1414, 1416 determine that they are inthe user equipment group 1622 being paged (because bit 4 of the userequipment indication information is set to 1), so each of the userequipment 1412, 1414, 1416 prepare to send a response 1626 to the pagingindication. The response 1626 from each of the user equipment 1412,1414, 1416 may include an indication of the antenna port in which theeach user equipment is located. For example, each of the user equipment1412, 1414, 1416 may select a resource for transmission of the response1626 that corresponds to the antenna port where that user equipment islocated. For example, the user equipment 1412 may transmit the response1626 on a resource corresponding to antenna port 3. The user equipment1414 may transmit the response 1626 on a resource corresponding toantenna port 6. The user equipment 1416 may transmit the response 1626on a resource corresponding to antenna port 8.

In some embodiments, the user equipment 1412, 1414, 1416 may transmitthe response 1626 as a preamble on a random access channel (RACH). Insome situations, this preamble may be part of what would otherwise becalled a “request” on the random access channel. But in the presentexample, the user equipment 1412, 1414, 1416 may use the random accesschannel “request” in order to send the response 1626 to the base station1402.

The base station 1402 transmits a response 1628. The base station 1402may transmit the response 1628 as a random access response (RAR) messageon the same random access channel on which it receive the response 1526.The response 1628 may contain the paging message that the base station1402 is attempting to deliver to the user equipment being paged. Thatis, mode 1 and mode 3 differ, at least in that mode 1 transmits thepaging message on a standard paging channel (e.g., PCCH/PCH) whereasmode 3 transmits the paging message as part of a response on the randomaccess channel (RACH).

Based on the responses 1626, the base station 1402 can determine asubset of the total beam directions/antenna ports into which theresponse 1628 should be transmitted. In the present example, the basestation 1402 determines that the response 1628 only needs to betransmitted to beam directions/antenna ports 3, 6, and 8 of the 20 totalbeam directions/antenna ports, because all members of the user equipmentgroup 1622 being paged (i.e., user equipment group 4) are in those threedirections. As a result, the base station 1402 transmits the response1528 only to the antenna ports for the beam directions 3, 6, and 8.Because the user equipment 1412, 1414, 1416 are each in one of thedirections to which the response 1628 was transmitted, each of the userequipment 1412, 1414, 1416 will receive the response 1628.

In some embodiments, the response 1628 may contain an identifier foreach user equipment actually being paged, as well as a timing advanceindication and an uplink authorization. In the present example, theresponse 1628 would contain identifiers (e.g., S-TMSI) for the userequipment 1412 and the user equipment 1414. After receiving the response1628, each of the user equipment 1412, 1414, 1416 can determine if itwas being paged. The user equipment 1416 would determine that it is notbeing paged, because its identifier was not included in the response1628. Whereas the user equipment 1412, 1414 would each determine that itwas being paged, because its identifier was included in the response1628.

User equipment that determine that they are being paged may use thetiming advance indication and the uplink authorization in order toestablish access to the network. In particular, the user equipmentidentified in the response 1628 (e.g., the user equipment 1412, 1414)can continue to send a message 1630 according to the uplinkauthorization provided in the response 1628. The base station 1402 canthen transmit the message 1632 to confirm to each of the user equipment1412, 1414 that transmitted the message 1632 that it has successfullyaccessed the network. That is, mode 2 and mode 3 differ, at least inthat mode 2 uses the RAR (the response 1528) to identify the userequipment being paged, whereas mode 3 uses the RAR (the response 1628)to both identify the user equipment being paged and provide uplinkauthorization for the subsequent network access needed by the paged userequipment.

FIG. 17 is a flowchart of a process 1700 for paging transmission usingmultiple paging transmission modes. The process 1700 may be performed bya base station (e.g., as described for base station 102, 302, 402, 502,1402, wireless communication apparatus 200) in communication with one ormore user equipment (e.g., as described for user equipment 106, 312,404, 512, 1412, wireless communication apparatus 200).

Prior to beginning the process 1700, the base station may determine thatit is necessary to page specific user equipment (e.g., the networknotifies the base station of an incoming call for the user equipment).Though not depicted in the process 1700, the base station may determinea user equipment group based on the user equipment that is to be paged(e.g., as described with respect to user equipment group 1422).

At block 1702, the base station determines a paging transmission mode.The base station may determine the paging transmission mode by selectingone transmission mode from a group of available transmission modes(e.g., modes 1, 2, and 3 as described herein). A transmission mode maybe considered “available” to the base station if the transmission modeinvolves a sequence of communications which the base station isconfigured and/or capable of performing.

The base station may determine the paging transmission mode using any ofa variety of factors. For example, the base station may choose a pagingtransmission mode that is predefined as a default paging transmissionmode. As another example, the base station may choose a pagingtransmission mode based on the expected number of user equipment in theuser equipment group that is to be paged. For instance, modes 1 and 2may be more efficient for paging a user equipment in a large group ofuser equipment (e.g., because contention in mode 3 would result in manycollision and thus would be inefficient), whereas mode 3 may be moreefficient for paging a user equipment in a small group of user equipment(e.g., because random access established as part of pagingtransmission). As another example, the network may indicate to the basestation what paging transmission mode to use.

At block 1704, the base station transmits a paging indication. The basestation may transmit the paging indication as described elsewhere herein(e.g., as described with respect to paging indication 1424, 1524, 1624).One or more user equipment located in more than one antenna port for thebase station may receive the paging indication. The user equipment thatreceive the paging indication may use user equipment indicationinformation contained in the paging indication in order to determine ifthe user equipment is part of a group that is being triggered to providea response.

At block 1706, the base station receives one or more responses from userequipment. In particular, all user equipment in the groups identified bythe user equipment indication information (transmitted as part of thepaging indication at the block 1704) may provide a response to the basestation using a message preamble transmitted on the random accesschannel. Each response received by the base station at the block 1706may include an indication of a beam direction/antenna port in which thesending user equipment is present.

At block 1708, the process 1700 branches based on which pagingtransmission mode was selected at the block 1702. If mode 1 wasselected, then the process 1700 continues at block 1710. If mode 2 wasselected, then the process 1700 continues at block 1712. If mode 3 wasselected, then the process 1700 continues at block 1714.

At block 1710, the base station transmits a paging message on the pagingchannel. The base station may transmit a standard paging message on astandard paging channel (e.g., PCCH/PCH). The base station may onlytransmit the paging message to those beam directions/antenna ports thatwere indicated by the responses received at the block 1706. The pagingmessage may include identification information for the user equipmentbeing paged. Each of the user equipment that receive the paging messagemay use the identification information to determine if it is beingpaged. After the completion of the block 1710, the user equipment thatis being paged has completed paging, but the user equipment has yet toestablish uplink access over a random access channel (e.g., RACH) (block1724).

At block 1712, the base station transmits a response message with theidentifier for the user equipment being paged. The base station maytransmit the response as a random access response (RAR) on the samerandom access channel on which the responses were received at the block1706. The response may include identification information for the userequipment being paged. Each of the user equipment that receive theresponse may use the identification information to determine if it isbeing paged. After the completion of the block 1712, the user equipmentthat is being paged has completed paging, but the user equipment has yetto establish uplink access over a random access channel (e.g., RACH)(block 1724).

At block 1714, the base station transmits a response message with theidentifier for the user equipment being paged as well as uplinkauthorization information. The base station may transmit the response asa random access response (RAR) on the same random access channel onwhich the responses were received at the block 1706. The response mayinclude identification information for the user equipment being paged.Each of the user equipment that receive the response may use theidentification information to determine if it is being paged.

At block 1716, the base station receives one or more uplink responses.The base station may receive the one or more uplink responses on thesame random access channel on which the responses were received at theblock 1706 and on which the responses was transmitted at the block 1714.In particular, the responses received at the block 1716 may be randomaccess messages made by the user equipment that are being paged in orderto secure access to the network on the uplink random access channel. Theuser equipment may use the uplink authorization information transmittedby the base station at the block 1714 to send the response received bythe base station at the block 1716.

At block 1718, a determination is made as to whether the uplink responsereceived at the block 1716 was successful or not. In particular, as auser equipment that is being paged attempts to send a response on theuplink random access channel, it will be contending for resources onthat channel with other user equipment. If the user equipment succeedsin contending for the uplink random access channel, then the process1700 continues at block 1720. If the user equipment does not succeed incontending for the uplink random access channel, then the user equipmentthat is being paged has completed paging, but the user equipment has yetto establish uplink access over a random access channel (e.g., RACH)(block 1724).

At block 1720, the base station transmits a response to the userequipment to notify the user equipment of its success in contending forthe uplink random access resources. The base station may transmit theresponse at block 1720 on the same random access channel on which theresponses were received at the block 1706, on which the responses wastransmitted at the block 1714, and on which the responses were receivedat the block 1716. After the completion of the block 17120, the userequipment that is being paged has completed paging, and the userequipment has also established uplink access over a random accesschannel (e.g., RACH) (block 1722).

In some embodiments, the paging indication transmitted at the block 1704may include paging transmission mode indication information. Forexample, the paging indication may include a two bit identifier of thepaging transmission mode (as selected at the block 1702) for each userequipment group. For instance, if there are eight user equipment groups,there may be 16 bits allocated to indicating the paging transmissionmode for the user equipment groups. In such embodiments, the two bitsmay indicate the paging transmission mode being used (e.g., 01=mode 1,10=mode 2, 11=mode 3). As such, a user equipment that is a member of auser equipment group indicated by the user equipment indicationinformation in the paging indication may use the two bits correspondingto its user equipment group to determine how it should proceed withsubsequent paging activity (e.g., monitor the paging channel for mode 1,monitor the random access channel for modes 2 and 3). Alternatively, asingle paging transmission mode indication may be used for all userequipment groups, in which case all user equipment may use the sameindicated paging transmission mode.

FIG. 18 is a flowchart of a process 1800 for paging transmission usingmultiple paging transmission modes. The process 1700 may be performed bya base station (e.g., as described for base station 102, 302, 402, 502,1402, wireless communication apparatus 200) in communication with one ormore user equipment (e.g., as described for user equipment 106, 312,404, 512, 1412, wireless communication apparatus 200). The process 1800may be provided substantially as described with respect to the process1700, with like reference numerals indicating like elements.Distinctions between the process 1700 and the process 1800 are notedbelow.

At block 1802, the base station determines a paging transmission mode.The base station may determine the paging transmission mode by selectingone transmission mode from a group of available transmission modes(e.g., modes 2 and 3 as described herein). A transmission mode may beconsidered “available” to the base station if the transmission modeinvolves a sequence of communications which the base station isconfigured and/or capable of performing. As opposed to the block 1702 inthe process 1700, the block 1802 in the process 1800 may involve thebase station selecting a paging transmission mode from a smaller numberof available transmission modes. There may be fewer paging transmissionmodes available due to a smaller number of paging transmission modessupported by the base station or the user equipment with which it is incommunication. The base station may determine the paging transmissionmode using any of a variety of factors, such as the exemplary factorsdescribed for the block 1702.

At block 1808, the process 1800 branches based on which pagingtransmission mode was selected at the block 1802. If mode 2 wasselected, then the process 1800 continues at block 1712. If mode 3 wasselected, then the process 1800 continues at block 1714.

It should be understood that embodiments described herein may be usedwith more or fewer paging transmission modes than those describedherein.

From the foregoing, it will be appreciated that specific embodiments ofthe invention have been described herein for purposes of illustration,but that various modifications may be made without deviating from thescope of the invention. Accordingly, the invention is not limited exceptas by the appended claims.

The disclosed and other embodiments, modules and the functionaloperations described in this document can be implemented in digitalelectronic circuitry, or in computer software, firmware, or hardware,including the structures disclosed in this document and their structuralequivalents, or in combinations of one or more of them. The disclosedand other embodiments can be implemented as one or more computer programproducts, i.e., one or more modules of computer program instructionsencoded on a computer readable medium for execution by, or to controlthe operation of, data processing apparatus. The computer readablemedium can be a machine-readable storage device, a machine-readablestorage substrate, a memory device, a composition of matter effecting amachine-readable propagated signal, or a combination of one or morethem. The term “data processing apparatus” encompasses all apparatus,devices, and machines for processing data, including by way of example aprogrammable processor, a computer, or multiple processors or computers.The apparatus can include, in addition to hardware, code that creates anexecution environment for the computer program in question, e.g., codethat constitutes processor firmware, a protocol stack, a databasemanagement system, an operating system, or a combination of one or moreof them. A propagated signal is an artificially generated signal, e.g.,a machine-generated electrical, optical, or electromagnetic signal, thatis generated to encode information for transmission to suitable receiverapparatus.

A computer program (also known as a program, software, softwareapplication, script, or code) can be written in any form of programminglanguage, including compiled or interpreted languages, and it can bedeployed in any form, including as a stand alone program or as a module,component, subroutine, or other unit suitable for use in a computingenvironment. A computer program does not necessarily correspond to afile in a file system. A program can be stored in a portion of a filethat holds other programs or data (e.g., one or more scripts stored in amarkup language document), in a single file dedicated to the program inquestion, or in multiple coordinated files (e.g., files that store oneor more modules, sub programs, or portions of code). A computer programcan be deployed to be executed on one computer or on multiple computersthat are located at one site or distributed across multiple sites andinterconnected by a communication network.

The processes and logic flows described in this document can beperformed by one or more programmable processors executing one or morecomputer programs to perform functions by operating on input data andgenerating output. The processes and logic flows can also be performedby, and apparatus can also be implemented as, special purpose logiccircuitry, e.g., an FPGA (field programmable gate array) or an ASIC(application specific integrated circuit).

Processors suitable for the execution of a computer program include, byway of example, both general and special purpose microprocessors, andany one or more processors of any kind of digital computer. Generally, aprocessor will receive instructions and data from a read only memory ora random access memory or both. The essential elements of a computer area processor for performing instructions and one or more memory devicesfor storing instructions and data. Generally, a computer will alsoinclude, or be operatively coupled to receive data from or transfer datato, or both, one or more mass storage devices for storing data, e.g.,magnetic, magneto optical disks, or optical disks. However, a computerneed not have such devices. Computer readable media suitable for storingcomputer program instructions and data include all forms of non-volatilememory, media and memory devices, including by way of examplesemiconductor memory devices, e.g., EPROM, EEPROM, and flash memorydevices; magnetic disks, e.g., internal hard disks or removable disks;magneto optical disks; and CD ROM and DVD-ROM disks. The processor andthe memory can be supplemented by, or incorporated in, special purposelogic circuitry.

While this document contains many specifics, these should not beconstrued as limitations on the scope of an invention that is claimed orof what may be claimed, but rather as descriptions of features specificto particular embodiments. Certain features that are described in thisdocument in the context of separate embodiments can also be implementedin combination in a single embodiment. Conversely, various features thatare described in the context of a single embodiment can also beimplemented in multiple embodiments separately or in any suitablesub-combination. Moreover, although features may be described above asacting in certain combinations and even initially claimed as such, oneor more features from a claimed combination can in some cases be excisedfrom the combination, and the claimed combination may be directed to asub-combination or a variation of a sub-combination. Similarly, whileoperations are depicted in the drawings in a particular order, thisshould not be understood as requiring that such operations be performedin the particular order shown or in sequential order, or that allillustrated operations be performed, to achieve desirable results.

Only a few examples and implementations are disclosed. Variations,modifications, and enhancements to the described examples andimplementations and other implementations can be made based on what isdisclosed.

What is claimed is:
 1. A wireless communication method, comprising:mapping, by a base station, an indication information to one or moreresource elements, wherein the one or more resource elements areresource elements in one or more synchronization signal symbols that arenot mapped by a synchronization signal, wherein the indicationinformation includes paging downlink control information and schedulinginformation of remaining minimum system information, wherein theindication information comprises user equipment indication information,and wherein the user equipment is paged using the user equipmentindication information; transmitting the indication information to auser equipment, wherein the transmitting the indication information isperformed in a sweeping mode on all antenna ports in all beam directionsin response to the indication information including the user equipmentindication information.
 2. The method of claim 1, wherein the one ormore resource elements comprise one or more continuous pluralities ofresource elements without a demodulation reference signal mapped to aresource element of the continuous plurality of resource elements, andwherein the method further comprises: mapping a demodulation referencesignal to one or more resource elements in one or more physicalbroadcast channel symbols that are adjacent to at least one of the oneor more synchronization signal symbols, wherein the indicationinformation shares a same antenna port with the physical broadcastchannel.
 3. The method of claim 1, wherein the one or more resourceelements are outside a bandwidth of the one or more synchronizationsignals, and wherein the one or more resource elements are inside abandwidth of one or more physical broadcast channels.
 4. The method ofclaim 1, wherein the indication information comprises an indicator of apaging transmission mode, wherein the paging transmission mode is a modeby which a paging downlink control information and/or paging message isto be transmitted, and wherein the method further comprises: selectingthe paging transmission mode from among a plurality of availabletransmission modes.
 5. The method of claim 1, wherein the indicationinformation comprises a paging reason category indication information,wherein the paging reason category indication information indicates areason for which the indication information is being transmitted.
 6. Themethod of claim 1, further comprising: receiving one or more responsesto the indication information from one or more user equipment; andtransmitting one or more paging messages based on information receivedin the one or more responses.
 7. The method of claim 1, furthercomprising: transmitting the indication information using a plurality ofantenna ports; receiving one or more responses to the indicationinformation from one or more user equipment, each response indicating atleast one antenna port; and transmitting one or more paging messagesusing the antenna ports indicated in the responses.
 8. The method ofclaim 1, further comprising: determining a group of user equipment towhich one or more user equipment to page belong, wherein the indicationinformation includes an indicator for the group of user equipment. 9.The method of claim 1, further comprising: receiving the indicationinformation, the indication information including an indicator for agroup of user equipment determined based on incoming data informationindicating a user equipment to page.
 10. A wireless communicationmethod, comprising: receiving, by a user equipment, an indicationinformation in one or more resource elements, wherein the one or moreresource elements are resource elements in one or more synchronizationsignal symbols that are not mapped by a synchronization signal, whereinthe indication information includes paging downlink control informationand scheduling information of remaining minimum system information,wherein the indication information comprises user equipment indicationinformation, and wherein the user equipment is paged using the userequipment indication information, and wherein a transmission of theindication information is in a sweeping mode on all antenna ports in allbeam directions in response to the indication information including theuser equipment indication information; and transmitting a response tothe indication information received by the user equipment.
 11. Themethod of claim 10, wherein the one or more resource elements compriseone or more continuous pluralities of resource elements without ademodulation reference signal mapped to a resource element of thecontinuous plurality of resource elements, and wherein the methodfurther comprises: receiving a demodulation reference signal in one ormore resource elements in one or more physical broadcast channel symbolsthat are adjacent to at least one of the one or more synchronizationsignal symbols, wherein the indication information shares a same antennaport with the physical broadcast channel.
 12. The method of claim 10,wherein the one or more resource elements are outside a bandwidth of theone or more synchronization signals, and wherein the one or moreresource elements are inside a bandwidth of one or more physicalbroadcast channels.
 13. The method of claim 10, wherein the indicationinformation comprises an indicator of a paging transmission mode,wherein the paging transmission mode is a mode by which a pagingdownlink control information and/or paging message is to be transmitted,and wherein the paging transmission mode is from a plurality ofavailable transmission modes.
 14. The method of claim 10, wherein theindication information comprises a paging reason category indicationinformation, wherein the paging reason category indication informationindicates a reason for the transmission of the indication information.15. The method of claim 10, further comprising: receiving one or morepaging messages based on information transmitted in the response. 16.The method of claim 10, further comprising: receiving the indicationinformation in a space corresponding to one antenna port of a pluralityof antenna ports over which the indication information was transmitted;wherein the response indicates at least one antenna port; and receivingone or more paging messages in a space corresponding to one of the atleast one indicated antenna ports, the one or more paging messagestransmitted using the antenna ports indicated in the responses.
 17. Awireless communication apparatus, comprising a processor configured to:map, by a base station, an indication information to one or moreresource elements, wherein the one or more resource elements areresource elements in one or more synchronization signal symbols that arenot mapped by a synchronization signal, wherein the indicationinformation includes paging downlink control information and schedulinginformation of remaining minimum system information, wherein theindication information comprises user equipment indication information,and wherein the user equipment is paged using the user equipmentindication information; transmit the indication information to a userequipment, wherein the transmit the indication information is performedin a sweeping mode on all antenna ports in all beam directions inresponse to the indication information including the user equipmentindication information.
 18. The wireless communication apparatus ofclaim 17, wherein the one or more resource elements comprise one or morecontinuous pluralities of resource elements without a demodulationreference signal mapped to a resource element of the continuousplurality of resource elements, and wherein the processor is furtherconfigured to: map a demodulation reference signal to one or moreresource elements in one or more physical broadcast channel symbols thatare adjacent to at least one of the one or more synchronization signalsymbols, wherein the indication information shares a same antenna portwith the physical broadcast channel.
 19. The wireless communicationapparatus of claim 17, wherein the one or more resource elements areoutside a bandwidth of the one or more synchronization signals, andwherein the one or more resource elements are inside a bandwidth of oneor more physical broadcast channels.
 20. The wireless communicationapparatus of claim 17, wherein the indication information comprises anindicator of a paging transmission mode, wherein the paging transmissionmode is a mode by which a paging downlink control information and/orpaging message is to be transmitted, and wherein the processor isfurther configured to: select the paging transmission mode from among aplurality of available transmission modes.
 21. A wireless communicationapparatus, comprising: a processor configured to: receive, by a userequipment, an indication information in one or more resource elements,wherein the one or more resource elements are resource elements in oneor more synchronization signal symbols that are not mapped by asynchronization signal, wherein the indication information includespaging downlink control information and scheduling information ofremaining minimum system information, wherein the indication informationcomprises user equipment indication information, and wherein the userequipment is paged using the user equipment indication information, andwherein a transmission of the indication information is in a sweepingmode on all antenna ports in all beam directions in response to theindication information including the user equipment indicationinformation; and transmit a response to the indication informationreceived by the user equipment.
 22. The wireless communication apparatusof claim 21, wherein the one or more resource elements comprise one ormore continuous pluralities of resource elements without a demodulationreference signal mapped to a resource element of the continuousplurality of resource elements, and wherein the processor is furtherconfigured to: receive a demodulation reference signal in one or moreresource elements in one or more physical broadcast channel symbols thatare adjacent to at least one of the one or more synchronization signalsymbols, wherein the indication information shares a same antenna portwith the physical broadcast channel.
 23. The wireless communicationapparatus of claim 21, wherein the indication information comprises anindicator of a paging transmission mode, wherein the paging transmissionmode is a mode by which a paging downlink control information and/orpaging message is to be transmitted, and wherein the paging transmissionmode is from a plurality of available transmission modes.